A novel means of maintaining the sterility of ophthalmic solutions is proposed wherein a membrane type dispenser is employed to provide sterile preservative free solutions. The device protects a sterile solution through the use of a specially treated membrane that prevents the growth of micro organisms from the septic side of the bottle. The proposed dispenser maintains sterility by employing two distinct mechanisms, these being the filtration of pathogens from a solution through physical exclusion, as related to the size of the pores of the membrane. Secondly, and most importantly, pathogens cannot "grow- through" the membrane because it is chemically treated to be toxic to such pathogens.